HDD power tools: the sander

At first we thought this looked hastily thrown together and quite possible useless. Then we watched the video, embedded after the break, and realized it is quite a handy bench sander. [Mhkabir] opened up an older hard drive, removed the read head, and added a piece of carefully cut sand paper. When you hook it up to your bench supply you’ve got a small sander ready to use. We can’t wait to try it on some small PCB edges. Now that we’ve seen a sander and a chop saw, we wonder what’s next?

it may not have a ton of torque, but its looks handy enough for small jobs, and if your like me (in an apartment) where having a shop of good tools is not an option, this sure beats trying to do it by hand or keeping a dremel from walking all over the place

A HD motor might not have a lot of torque but if you fill the spindle with other old HD plats it will have plenty of inertia.
I would sand the plate when it is spinning, the glue it to the sandpaper and the cut it to shape.

The “Reason” someone puts a sanding disk on a Hard Drive platter is simply put: THEY are proudly a HACKER!

Which is what separates many of us from NON- Hackers.

The people who see that HD turned into a Sander and immediately think of how totally NEAT it would be to either have one Hacked like that- or do something inspired by what Mhkabir did? Ah, That’s how a Hacker discovers anew that Hacking is a Mindset. WE get a kick out of seeing something that catches our imagination.

The mundanes and not-quite Hackers spend more time as a GROUP slagging such a Hack than it likely took to make it.

The Real Hackers among us- like me- and those of you who think the same way as Mhkabir are why HaD and Hackerspaces exist at all. At least it’s what *I* feel separates Hackers from mundanes- and Hackers needing to think before disrespecting.

We tend to be immediately mumbling “Where did I put that box of old HD’s” instead of Peanut Gallery heckling every freckle on the latest HaD featured Hack.

Yes- there’s always valid Constructive Commentary to be shared and even welcomed. The destructive, disrespectful slagging I see on many HaD comment threads is simply not doing anything helpful. I feel that Mhkabir has gifted Hackerdom with something we owe RESPECT for.

Can’t find the original (Afrotech, maybe?), but this hack was done by someone else years ago. A guy named Jipa in 2006, also. Cool hack, but Mhkabir is not the originator. Whoever did the older page I saw, he was using it to sharpen scalpel blades, and that inspired me to build a similar rig for sharpening my #11 X-acto blades with self-adhesive 1000-grit paper on an old scsi drive.

The drive does shut itself off after about 10-15 seconds, but that’s usually enough time to do a blade. There isn’t much torque, so I think there are better solutions out there for doing any kind of sanding work, but for finishing a blade it’s fantastic.

@ Oren Beck: “The mundanes…”
Way to reinforce the elitist nerd image. Why not just go for broke and use the term “muggles”.

Yeah- I might have chosen a more elegant sort of phrasing. Or- you could have snipped the “someone else did it first” comments. Sorry in advance for the momentary confusion my saying that will cause.

See- I never said Mhkabir was the first/only to do that Hack. What my comments were-and ARE intended to convey is more respectful of a larger picture.

But- there’s a few deeper layers :)

You were indeed right to catch my “coulda done better” misphrasing. That’s an Attaboy earned rightly by you to offset my Oops in the Perceptions scorecard.

Then? ALL of us seem to have forgotten the last words about why what we say about each other’s posted Hacks matters.

Mhkabir made his incarnation of that Hack catch the attention of HaD and it got Featured. That’s a thing which also is not diminishing to anyone else’s Hacks, nor should his be disrespected for not being “first”

another trick is to locate where the head driver chip is, measure which pin goes “low” or “high” when it shuts down then connect it via resistor to the inverse voltage.

this also works for CDROM drives, the main chip on many of these is identical and relatively easy to hack, as well as being able to feed a valid stored data stream (captured from the drive pre-gutting) into the eye pattern test point. As long as you keep feeding it the pattern it will keep spinning with the side effect of the pattern speed determining the rotation speed.

the onboard stepper motor can then be controlled using the up/down inputs on the driver chip.

interestingly, many of the old style <10GB drives can be more useful as the motors are lower speed but higher torque.

michiel145 – shame on you, its not a hack my ass, i’ll make a lapidary wheel to facet glass art marbles off a hard drive now as a direct result of this awesome creative project. lay off the labeling beans bummer mc bummerson, thanks for sharing this mike

Hack-a-Day actually covered this about 2 years ago. Most comments were in support of how potentially dangerous using this hack might be. The original post was here ->http://hackaday.com/2008/06/27/turn-your-old-hard-drive-into-a-sandergrinder/. I would caution the use of this hack in the exact same way I did before. Any of you that have ever ever experienced a head crash on a hard drive, and taken it apart to see the damage can relate. Also please keep in mind how light and flimsy the head is in a hard drive. Check out the link below to see what this flimsy little head can do to a hard drive platter, then imagine what it would look like if you actually applied force to the platter. While the platters in your hard drive may seem to be really hard, they weren’t engineered to have any friction applied to them. Do you really want to take a chunk of a HD platter in the face, or even hand for that matter? I’m done with the soap box, and now for the link to what a flimsy drive head failure can do to your new sander – http://gfx.ibas.com/news/pictures/total_head_crash.jpg

chill my friend. I have seen quite a few hard drives that have died in that manner.

That damage is not from a single head strike. There is no where near enough kinetic energy in the platters (low mass, low torque) for that damage to occur immediately.

That damage is caused by a head coming UNGLUED from the arm, and then the arm abrading away at the platters for 100’s of hours. Not split seconds, seconds or minutes, but hours and hours.

You see drives like that NOT from homes where a damaged drive is immediately apparent, but from multi drive raid arrays where a dead drive may often be left running for extended periods before being pulled from service.

I have one in my drawer here at work still. The admins said the drive was noisy for weeks before it fell silent.